So this post looks at whether SaskPower's view, that wind and solar are only marginal generators, is valid.

Spoiler: it is not and here is why;

Every month the US Energy Information Administration publishes details on how much electricity each state generates and what fuels are used to generate that power. It's a gripping read - so if you are not already familiar with the EIA's 'Electric Power Monthly', check it out: more stats than you can shake a stick at.

By sifting through each monthly data set it is possible to see how much of each state's total electricity needs are met by wind turbines and solar panels. By going back through several years of data it is possible to find the maximum percentage of total monthly electricity generation which was met by wind and solar. The results will surprise some folk - especially the 'small scale' proponents;

Source: US Energy Information Administration - Electric Power Monthly (multiple editions). Note - this graph does not account for the fact that the US EIA data only includes industrial-scale (i.e. > 1MW) solar projects. Inclusion of Commercial and Residential could increase the total by 50 percent.

Five things to note from this;

System reliability. No surprises regarding the top four states - Iowa, South Dakota, Kansas and Idaho - which are also top in the annual rankings. But what is noteworthy is the very high monthly penetrations being achieved especially in Iowa and South Dakota. Both have recorded levels of wind generation, for an entire month, in excess of 40 percent of total generation: in November 2014 and March 2015 respectively. Despite these high levels the entities concerned with system reliability - MISO in Iowa and the South Dakota Public Utilities Commission - have not registered any concerns.

In other words: despite what SaskPower would have you believe, life as we know it does not end at wind penetrations in excess of 10 percent. Neither at 40 percent it would seem.

Inflexible baseload and wind energy. Saskatchewan in 2014 generated 44 percent of its electricity using coal capacity. Proponents of maintaining the status quo frequently note that inflexible, baseload coal capacity is ill-suited to dealing with variable wind and solar output. Consequently, according to that logic, variable renewables must be limited in order to 'keep the lights on'. In fact this is one of the major conclusions of a SaskPower-funded Conference Board of Canada report released earlier this month. It proposed a cap of 10 percent on wind energy in Saskatchewan (and Alberta). We examine that report in a separate post. There is however no evidence to suggest that large amounts of coal-fired baseload justifies the need to impose extremely low limits on wind and solar power. Here is why...

Two states in the previous graph (North Dakota and Iowa) have very high penetrations of inflexible, baseload coal-fired generating capacity. In 2014 North Dakota generated 74 percent of its total electricity needs from coal - the comparable figure for Iowa was 54 percent. For details check out this excellent Washington Post interactive.

Both of these levels are significantly higher than the 44 percent which coal contributes to Saskatchewan electricity demand.

Despite these very high coal penetrations both North Dakota and Iowa have recorded, as shown above, very high monthly penetrations of generation entirely from wind energy: 22.1 percent in May 2015 for North Dakota and 42.2 percent in November 2014 for Iowa. Check out this post for 2014 annual data.

In other words: high penetrations of wind energy are possible even on systems with high levels of old, inflexible coal-fired baseload. This information further suggests that, even with coal currently generating 44 percent of our electricity, Saskatchewan could support having at least 30 percent of its electricity generated by wind turbines. FYI: 30 percent is the annual wind penetration which will be reached by Iowa at the end of 2015 and it is more than ten times greater than wind's current penetration in Saskatchewan (2.7 percent).

Solar. Following rapid growth in the last few years, solar is now emerging as a major generator in its own right. For the entire month of May wind and solar together generated 20.6 percent of California's total generation. Of that amount wind was responsible for 10.9 percent and solar 9.7 percent. In fact the record for solar alone was in the prior month, April 2015, when solar generated 10.0 percent of the state's total (nb: the actual solar generation figure could be 50 percent higher - see the 'health warning' in the graph above).

Not too shabby and, surprise surprise, the lights stayed on in California. Also of note: earlier this month the California Senate passed a bill mandating that by 2030 half of all of California's electricity will have to be generated from renewables: most of that will be wind and solar.

..and in case you are wondering... Vermont in May saw 23.2 percent of its generation from wind which may seem odd since it did not even register in the 2014 Top-10. The reason for this apparent discrepancy is that in December 2014 the Vermont Yankee nuclear power station was closed and as a result wind output in 2015 is now a significant component of total in-state generation.

These record monthly penetrations of wind and solar energy by state should have demonstrated two key facts to even the most sceptical;

1) Marginal generators no more. Wind and solar cannot justifiably be restricted to a marginal role in power generation in Saskatcheawn (or Alberta). Wind energy already makes up more than 40 percent of monthly penetrations in some states (Iowa and South Dakota). In April this year Solar generated 10 percent of California's total electricity. These amounts are only increasing as the cost of both forms of generation continues to fall.

2) Inflexible coal baseload - not as restrictive as claimed. Two states in particular (Iowa and North Dakota) have demonstrated that high penetrations of legacy coal cannot be used as justification for imposing ridiculously low constraints on wind and solar power in Saskatchewan (or Alberta).

In short - this is yet more evidence that SaskPower is right to be moving beyond its default position of blind resistance to wind and solar (see this post). As a next step it should be more willing to engage in serious dialogue with the renewable energy community. Who knows - it may surprise itself and learn something!